Elastomeric centralizer base for rock drilling system

Abstract

A rock drilling system comprising a rock drill adapted to hold a drill steel to which a drill bit is connected, a drill feed rail for slidably supporting a drill feed that displaces the rock drill along the drill feed rail, a stinger-supported centralizer assembly for centralizing the drill steel, wherein the stinger-supported centralizer assembly has a centralizer base made of an elastomeric material, and a travelling cradle centralizer assembly slidable over the drill feed rail for centralizing the drill steel, wherein the travelling cradle centralizer assembly has a cradle made of an elastomeric material.

The invention claimed is: 
     
       1. A rock drilling system comprising:
 a rock drill adapted to hold a drill steel to which a drill bit is connected; 
 a drill feed rail for slidably supporting a drill feed that displaces the rock drill along the drill feed rail; 
 a stinger-supported centralizer assembly for centralizing the drill steel, wherein the stinger-supported centralizer assembly has a centralizer base made of an elastomeric material; and 
 a travelling cradle centralizer assembly slidable over the drill feed rail for centralizing the drill steel, wherein the travelling cradle centralizer assembly has a cradle made of an elastomeric material. 
 
     
     
       2. The system as claimed in  claim 1  wherein the centralizer base of the stinger-supported centralizer assembly includes an integrally formed stinger pad. 
     
     
       3. The system as claimed in  claim 2  wherein the travelling cradle centralizer assembly comprises an elastomeric base integrally formed with the cradle. 
     
     
       4. The system as claimed in  claim 1  wherein the travelling cradle centralizer assembly comprises an elastomeric base integrally formed with the cradle. 
     
     
       5. The system as claimed in  claim 1  further comprising a heat guard made of a heat-insulating material fastened to an upper portion of the centralizer base of the stinger-supported centralizer assembly. 
     
     
       6. The system as claimed in  claim 5  further comprising a bushing fastened to the centralizer base with the heat guard fastened between the bushing and the centralizer base. 
     
     
       7. The system as claimed in  claim 1  wherein the elastomeric material of both the centralizer base and the cradle is urethane. 
     
     
       8. A stinger-mounted centralizer assembly comprising:
 a stinger pad; 
 a centralizer base made of an elastomeric material, the base having a lower portion that includes a bore fully surrounded by the lower portion and dimensioned to receive a hydraulically extendable stinger rod to which the stinger pad is mounted, wherein the base also has an upper portion that includes a bushing support defining an upwardly facing round trough; and 
 a bushing supported by the rough trough and fastened to the bushing support, wherein the bushing is dimensioned to receive a drill steel. 
 
     
     
       9. The stinger-mounted centralizer assembly as claimed in  claim 8  further comprising a heat guard made of a heat-insulating material fastened between the bushing and the bushing support. 
     
     
       10. The stinger-mounted centralizer assembly as claimed in  claim 8  wherein the stinger pad is movable relative to the base. 
     
     
       11. The stinger-mounted centralizer assembly as claimed in  claim 8  wherein the stinger pad is integrally formed with the base whereby the base moves with the pad. 
     
     
       12. A travelling cradle centralizer assembly comprising:
 a cradle made of an elastomeric material, the cradle being slidable over a feed rail; 
 a base mounted on the cradle, the base having an upper portion that includes a bushing support defining a round trough; 
 a bushing fastened to the bushing support, wherein the bushing is dimensioned to receive a drill steel. 
 
     
     
       13. The travelling cradle assembly as claimed in  claim 12  wherein the base is fastened to the cradle. 
     
     
       14. The travelling cradle assembly as claimed in  claim 12  wherein the base is integrally formed with the cradle. 
     
     
       15. The travelling cradle assembly as claimed in  claim 14  wherein the elastomeric material is urethane. 
     
     
       16. The travelling cradle assembly as claimed in  claim 15  further comprising a heat guard made of a heat-insulating material fastened between the bushing and the bushing support. 
     
     
       17. The travelling cradle assembly as claimed in  claim 12  further comprising a heat guard made of a heat-insulating material fastened between the bushing and the bushing support. 
     
     
       18. The travelling cradle assembly as claimed in  claim 12  wherein the elastomeric material is urethane.